Joint Link Scheduling and Rate Adaptation for Energy-Efficient Internet of Vessels

In the coming smart ocean era, reliable and efficient communications are crucial for promoting a variety of maritime activities. While on-shore base stations (BSs) constitute a key infrastructure for maritime communications, the trap of low energy efficiency caused by long transmission distances must be delicately circumvented. In this paper, we try to utilize internet of vessels (IoV) to tackle the problem. Specifically, we investigate the joint link scheduling and rate adaptation problem for a maritime communication network with both shore-to-vessel and vessel-to-vessel links, with the target of minimizing the energy consumption while assuring a quality of service (QoS) guarantee for each vessel. With only large-scale channel state information available, the problem is shown to be an NP-hard mixed integer non-linear programming problem with a group of hidden nonlinear equality constraints. A process-oriented iterative scheme is proposed based on a relaxation and gradually-approaching method following the gentlest-ascent principle, as well as the divide-and-conquer strategy. Simulation results demonstrate that the proposed scheme can achieve a prominent gain in terms of network energy consumption reduction with a rather low complexity.